DAT Bootcamp Biology Exams (1-4) with Complete Solution

DAT Bootcamp Biology Exams (1-4) with Complete Solution modern cell theory - -All known living things are made up of one or more cells. All living cells arise from pre-existing cells by division. The cell is the fundamental unit of structure and function in all living organisms. The activity of an organism depends on the total activity of independent cells. Energy flow (metabolism and biochemistry) occurs within cells. Cells contain DNA which is found specifically in the chromosome and RNA found in the cell nucleus and cytoplasm. All cells are basically the same in chemical composition in organisms of similar species All cells contain a nucleus for the storage of genetic material. (T/F) - -False. Modern cell theory does not state that all cells contain a nucleus for storage of genetic material. Prokaryotes cells do not contain a nucleus. Instead, their genetic material is stored in the cytosol. The deregulation of apoptosis may lead to the development of various diseases. Which of these may develop from insufficient apoptosis? A. Alzheimer's disease B. Cancerous growth C. Parkinson's disease D. Turner Syndrome E. Huntington's disease - -B. Cancerous growth Cancer is the result of uncontrolled cell proliferation. Apoptosis is programmed cell death, which functions both in normal cell development but is also a necessary part of destroying damaged and mutated cells that multiply uncontrollably. If apoptosis were to be deregulated, uncontrolled cell growths, including cancer, would be an expected result. Turner syndrome is an aneuploidy (specifically a monosomy) that is the result of a missing X chromosome due to nondisjunction in gamete formation during meiosis. - -Alzheimer's, Parkinson's, and Huntington's disease are neurodegenerative diseases, which are characterized by excessive apoptosis. A scientist wants to detach a peripheral membrane protein from the exterior of a cell membrane. Which is the best method to do so? A. Change the salt concentrations. B. Perform a light centrifuge. C. Add a detergent. D. Change the temperature of the solution. E. Run a small current through the solution. - -A. Change the salt concentrations. Peripheral membrane proteins are held in place by hydrogen bonding and electrostatic interactions. To detach such a protein from a cell membrane's exterior, one would need to disrupt these forces. There are two methods that will accomplish this task: changing the salt concentration, or changing the pH (altering the H+ concentration). A light centrifuge will precipitate cells and nuclei at most, only heavy centrifuges extract small soluble proteins. - -Adding a detergent is a method used to extract integral proteins because they are more hydrophobic in nature. The hydrophobic detergent will destroy the membrane and expose the hydrophobic integral protein. Changing the temperature will denature the protein. Running a current through the cell isn't a common or viable method. Miller-Urey Experiment - -The Miller-Urey experiment used ammonia, methane, water and hydrogen sealed in a sterile arrangement of tubes and flasks with connecting loops. After 2 weeks, they observed several organic compounds, a